A mixed-signal organic 1kHz comparator with low VT sensitivity on flexible plastic substrate

This paper presents a comparator that is designed in an organic electronics technology on a flexible plastic substrate with p-type organic thin-film transistors (p-OTFT) only. The comparator has a gain of 12dB and works at a supply voltage of 20V consuming 9µA. At a clock frequency of 1kHz the input sensitivity is 200mV. The comparator is designed following a threshold-voltage VT insensitive strategy for analog and mixed-signal design in a way to get round VT variations of the pentacene based organic electronics technology. Measurements have been done in ambient environment. The circuits still function well after several weeks of exposure to ambient environment. This comparator can serve in organic smart sensor systems as an interface between analog sensor signals and digital circuitry or as a building block for more complex A-to-D converters.